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Delay of gonadotropin stimulation in patients receiving gonadotropin-releasing hormone agonist (GnRH-a) therapy permits increased clinic efficiency and may enhance in vitro fertilization (IVF) pregnancy rates.

OBJECTIVE: To promote an even temporal distribution of patients starting IVF cycles at our center, patients undergoing GnRH agonist (GnRH-a) suppression frequently delay the start of gonadotropin stimulation. Our objective was to analyze the effect that the delay of initiation of gonadotropin stimulation has on outcome parameters in this population. DESIGN: Retrospective analysis. SETTING: A tertiary referral reproductive medicine unit. PATIENT(S): Patients undergoing IVF cycles on long GnRH-a protocols. INTERVENTION(S): Patients were treated with either a "standard-dose" or "low-dose" leuprolide acetate protocol initiated in the mid-luteal phase. MAIN OUTCOME MEASURE(S): Delay time, clinical pregnancy rate, ongoing pregnancy rate, cancellation rate. RESULT(S): Analysis of the overall group revealed associations between stimulation delay and decreases in stimulation duration and the number of gonadotropin ampules administered. Weighted linear regression analyzes revealed statistically positive relationships between delay time and both clinical pregnancy rates and ongoing pregnancy rates, despite a positive relationship between delay time and cancellation rates. Analysis of the standard-dose and low-dose subgroups revealed that the enhancement of pregnancy rates was attributable primarily to patients in the standard-dose protocol. CONCLUSION(S): Delay of gonadotropin stimulation while patients are receiving GnRH-a therapy allows for increased clinic efficiency. There appears to be an enhancement of clinical and ongoing pregnancy rates for the standard-dose leuprolide acetate protocol that is associated with stimulation delay.

Adult↗

Prediction of implantation by the sonographic appearance of the endometrium during controlled ovarian stimulation for in vitro fertilization (IVF)

The texture and the thickness of the endometrium as assessed by transvaginal sonography were prospectively evaluated in 123 patients undergoing IVF treatment. Three different types of endometrial patterns could be distinguished: (A) an entirely homogenous, hyperechogenic endometrium; (B) an intermediate type characterized by the same reflectivity of ultrasound as the myometrium, with a nonprominent or absent central echogenic line; and (C) a multilayered endometrium consisting of prominent outer and midline hyperechogenic lines and inner hypoechogenic regions. On the day before oocyte retrieval, endometrial thickness was significantly greater in the group of patients who achieved pregnancy than in the group who did not (8.7 +/- 0.4 vs 7.5 +/- 0.2 mm, respectively; P less than 0.01) and significantly more patients had multilayered, pattern C, endometrium (75% in pregnant women vs 42.4% in nonpregnant women; P less than 0.01). No pregnancy occurred when the endometrial thickness was less than 6 mm. When type C endometrium greater than or equal to 6 mm thick was seen, the pregnancy rate per embryo transfer was 39%. When type A or B endometrial pattern was seen, the negative predictive value for the occurrence of pregnancy was 90.5%. Our results suggest that transvaginal sonographic evaluation of endometrial texture and thickness may be an indicator of the likelihood of achieving pregnancy.

Adult↗

Estrone 3-glucuronide chemiluminescence immunoassay (LIA) and 17beta estradiol radioimmunoassay (RIA) in the monitoring of superovulation for in vitro fertilization (IVF): correlation with follicular parameters and oocyte maturity.

Many works in the literature of the last years had reported that urinary approach to superovulation study is a suitable method to evaluate ovarian response to pharmacological stimulation. Before applying urinary determination of hormonal levels with a chemiluminescence immuno assay (LIA) method in early morning urine (EMU) samples, we had studied the correlation of RIA-LIA procedures with reference to follicular volumes at hCG day and to recovered oocyte maturity; in fact follicular growth and oocyte morphological features are the main parameters to evaluate a successful induced cycle. In our department the IVF cycles are daily monitored with RIA seric E2 and LIA E1-3G determination, besides ultrasound examination of follicular growth. We have studied E2 and E1-3G levels on the hCG administration day and their correlation with follicular areas and volumes; moreover, we have evaluated hormonal values on oocyte pick-up day with reference to recovered oocyte number and maturity. We have assumed as good timing for oocyte pick-up when more than 50% of recovered oocytes were of good quality (maturity score 4). We have observed that the highest pre ovulatory E1-3G value is consistent with the best timing for oocyte pick-up; it's possible to obtain a conversion coefficient follicular volumes and urinary E1-3G excretion. We have not found significant differences between plasmatic and urinary estrogenic parameters. It is important to remember the advantages connected by a not isotopic and not invasive method. The absence of discomfort for the patients may be a decisive factor to choose the monitoring method and LIA procedure may represent a valid alternative to RIA.

Adult↗

Autologous endometrial coculture in patients with in vitro-fertilization (IVF) failure: correlations of outcome with leukemia inhibiting factor (LIF) production.

PROBLEM: To determine if LIF produced by autologous endometrial co-culture (ECC) was associated with outcome in 46 patients with a history of multiple IVF failures. METHOD OF STUDY: The conditioned media (CM) from ECC cells exposed or non-exposed to human embryos was analyzed for LIF. RESULTS: Exposure or non-exposure to an embryo did not result in differing levels of LIF in the CM. LIF levels were significantly greater in the CM than in the serum controls (LIF was not found in the serum controls). Embryos grown on ECC demonstrated a significant improvement in number of blastomeres and fragmentation when compared to embryos grown in conventional media without ECC (6.7 +/- 1.3 vs. 5.6 +/- 1.2 blastomeres and 17.6% +/- 9.3 vs. 26.4% +/- 9.8 fragmentation; P < 0.05). When LIF levels were detectable in the CM, the embryos grown in ECC were of improved quality as compared to the embryos grown only in conventional media and demonstrated a non-significant increase in pregnancy rates (60 vs. 48%, P = 0.50). CONCLUSIONS: We have demonstrated a significant improvement in embryo quality with ECC. The cells in the ECC express LIF. The presence of LIF in the CM was associated with embryonic development and clinical pregnancy.

Adult↗

Anesthesia practices in the United States common to in vitro fertilization (IVF) centers.

PURPOSE: Our purpose was to characterize and describe anesthesia practice in programs performing IVF in the United States. METHODS: We used a telephone survey requiring respondents to be either the program director, a physician, or a nurse familiar with the practice. Two hundred seven (78%) Society of Assisted Reproductive Technology (SART) registered programs agreed to participate. Programs were divided by geographic region and type of practice (academic versus private). RESULTS: Ninety-one private (68%) and 41 academic (56%) programs used personnel provided by the Department of Anesthesiology. Conscious sedation was performed most commonly (95%). The remaining 5% used primarily either general, regional, or local anesthesia. Typical recovery times were 90 to 120 min. Average costs of anesthetic administration were $300- $400 and were similar among groups except for the Eastern academic programs, with a higher mean cost of $543. Programs using personnel from anesthesiology reported higher costs compared to programs utilizing their own staff ($391 +/- 15 vs $157 +/- 11; P < 0.05). Complications were infrequent (< 10%); no hospitalizations or serious life-threatening incidents were reported. CONCLUSIONS: A large number of programs safely used their own trained personnel to deliver anesthesia, and realized a significant reduction in cost.

Academic Medical Centers↗

[A cytogenetic study of human oocytes unfertilized in in-vitro fertilization (IVF)].

A total of 260 unfertilized human oocytes obtained in our IVF program were studied cytogenetically, by a gradual fixation-air drying method proposed by Mikamo and Kamiguchi (1983). The oocytes were obtained from 72 cycles of 52 patients (mean age 32.1). Indications for these patients were 26 cases of tubal factor, 13 of male infertility, 2 of endometriosis and 11 of unexplained infertility. Ovulation induction was performed by hMG-hCG administration with GnRHa pretreatment. Of the 260 unfertilized oocytes, 183 displayed metaphase II and 149 were karyotyped accurately. There were 5 diploids (3.4%), 9 structural anomalies (6.0%) and 15 aneuploids (10.1%) including 8 hyperhaploids (5.4%) and 7 hypohaploids (4.7%). One hundred and twenty-two oocytes out of 149 (81.9%) were found to be normal haploids [23,X]. In 9 aneuploids, 5 showed the loss or gain of monads (so-called predivision), while 4 showed the loss or gain of dyads (so-called nondisjunction). Twenty-three oocytes out of 149 (15.4%) had one or more split dyads. (so-called nondisjunction). Twenty-three oocytes out of 149 (15.4%) had one or more split dyads. Our results were compared with those obtained in previous studies, and the importance of the chromosome preparation method in evaluating aberration frequencies was stressed. Causal mechanisms of aneuploidy, diploidy and structural anomaly were also discussed.

Adult↗

Plasma levels of free vascular endothelial growth factor(165) (VEGF(165)) are not elevated during gonadotropin stimulation in in vitro fertilization (IVF) patients developing ovarian hyperstimulation syndrome (OHSS): results of a prospective cohort study with matched controls.

OBJECTIVE: To evaluate whether differences in plasma vascular endothelial growth factor(165) (VEGF(165)) concentrations exist during gonadotropin stimulation in IVF patients developing severe ovarian hyperstimulation syndrome (OHSS) compared to matched controls. STUDY DESIGN: Prospective cohort study with comparison of 15 OHSS cases with 30 matched (age, follicle numbers, pregnancy) controls. Unpaired students t-test was used to evaluate differences between the OHSS and control group and correlations were calculated with Pearson's test. RESULT(S): Plasma levels of VEGF(165), at four time-points from start of gonadotropin stimulation to embryo transfer (ET), were compared and related to steroid levels and ultrasound data. There were no differences between OHSS and control patients in plasma VEGF(165) levels at any of the four time points, which were compared. The mean levels were between 53--83 pg ml(-1) and 64--83 pg ml(-1) in the OHSS and control group, respectively. Positive correlations existed between total number of follicles, number of large (>15 mm) follicles and VEGF(165) at day of oocyte aspiration and between VEGF(165) and progesterone at ET in the control group, but not in the OHSS group. CONCLUSION(S): Patients developing OHSS do not have raised plasma VEGF(165) levels during gonadotropin stimulation. The lack of positive correlation between VEGF(165) levels and follicle numbers/progesterone in the OHSS group, suggests a disruption in OHSS of the normal controlled follicular VEGF expression.

Adult↗

Effects of follicle stimulating hormone (FSH) on follicular development, oocyte retrieval, and in vitro fertilization (IVF) in ewes during breeding season and seasonal anestrus.

Administration of FSH increases the number of developing follicles, and affects oocyte health and cleavage rate. To determine the optimal level of FSH treatment, studies were conducted during the normal breeding season and seasonal anestrus. In Experiment 1, ewes were implanted with SyncroMate-B (SMB; norgestomet) for 14 days during the breeding season. Beginning on day 12 or 13 after SMB implantation, ewes were treated with saline (control; n=10), or treated with FSH for two days (2D; n=9) or three days (3D; n=10). In Experiment 2, conducted during seasonal anestrus, ewes were implanted with SMB for 14 days (n=23) or were not implanted (n=26). The SMB-implanted and nonimplanted ewes were assigned to one of three treatments as in Experiment 1: control (n=13), 2D (n=21) or 3D (n=15). In Experiments 1 and 2, ewes were laparotomized to count the number of follicles < or = 3 mm and > 3 mm and to retrieve oocytes. Healthy oocytes from each treatment were used for IVF. In Experiment 3, ewes (n=6) were implanted twice with SMB for 14 days during seasonal anestrus. Ewes were injected with FSH for 2 days, and the oocytes were collected and fertilized as in Experiments 1 and 2. In Experiment 1, FSH-treatment increased (P < 0.05) the number of follicles > 3 mm, the number of oocytes retrieved from follicles < or = 3 mm and > 3 mm, the proportion of healthy oocytes, and the number of oocytes used for IVF. Oocytes from control and 2D ewes had greater (P < 0.01) cleavage rates than 3D ewes (68% and 71% vs. 42%). In Experiment 2, implanted and nonimplanted ewes had similar (P > 0.05) numbers of follicles, total oocytes, and healthy oocytes; therefore, data were combined. The FSH treatment increased (P < 0.01) the number of follicles > 3 mm, and the number of oocytes recovered from follicles > 3 mm. The recovery rate of oocytes and the percentage of healthy oocytes were similar for control and FSH-treated ewes. The cleavage rate in Experiment 2 ranged from 4 to 16%. In Experiment 3, the cleavage rate for ewes treated twice with SMB was 27% which tended to be greater (P < 0.07) than for the 2D ewes that received one SMB implant in Experiment 2. These data indicate that FSH increased the number of developing follicles and the number of healthy oocytes retrieved from ewes during the breeding season and seasonal anestrus. However, cleavage rates during seasonal anestrus were lower than during the normal breeding season in both FSH-treated and control ewes. Treatment of ewes for 2 days with FSH resulted in a greater cleavage rate than treatment of ewes for 3 days.

Anestrus↗

Gonadotropin-releasing hormone agonist versus human chorionic gonadotropin for triggering follicular maturation in in vitro fertilization.

OBJECTIVE: To compare the use of gonadotropin-releasing hormone agonist (GnRH-a) with human chorionic gonadotropin (hCG) for triggering the final stage of follicular maturation for in vitro fertilization (IVF). DESIGN: In vitro fertilization outcome was determined in a randomized, prospective study. SETTING: The University of Toronto IVF program at The Toronto Hospital, Toronto General Division. PATIENTS AND INTERVENTIONS: One hundred seventy-nine women in the IVF program were given a subcutaneous injection of leuprolide acetate (500 micrograms) or an intramuscular injection of hCG (5,000 IU) 34 to 36 hours before oocyte retrieval. Vaginal progesterone (P) suppositories (50 mg) were used two times a day for luteal phase support. A subgroup of 41 women had serum estradiol (E2) and P levels determined 2 and 7 days after embryo transfer (ET). MAIN OUTCOME MEASURES: Pregnancy rates and luteal phase E2 and P were compared. RESULTS: In the GnRH-a group, there were 18 pregnancies from 84 ETs (20%). In the hCG group, there were 19 pregnancies from 95 ETs (19%). Luteal phase E2 and P levels were significantly lower in the GnRH-a group compared with the hCG group, and 18% of the former group had an apparent short luteal phase. CONCLUSIONS: Gonadotropin-releasing hormone agonist appears to be an effective alternative to hCG for inducing follicular maturation in IVF. The lower luteal phase E2 concentrations may potentially be beneficial in preventing ovarian hyperstimulation and for enhancing implantation. Better luteal phase support or a different dose of GnRH-a is needed to prevent luteal phase deficiency.

Chorionic Gonadotropin↗

Review of scientific contributions by the Belgian medical centers concerned with human in vitro fertilization and embryo transfer (IVF).

In vitro fertilization and embryo transfer (IVF) may be considered as a particular application of modern medical therapeutics linked to human reproduction. The treatment of human sterility therefore involves some fundamental human values such as life, love and death. The quality of this highly technological treatment with fast knowledge of outcome at the end of the patient's menstrual cycle has been evaluated since the early 80s. It is a typically multidisciplinary team effort involving medical doctors, biologists, laboratory technicians, nurses and clerks that is representative of modern medical practice. IVF covers much more than just embryology, as this review will explain. IVF developed in close relation with clinical and experimental research protocols, which are the major topics of this paper. The newness of the techniques used led to the necessary interactions between clinicians and biologists working on animal experimental embryology.

Academic Medical Centers↗

Fertilization potential in vitro is correlated with head-specific mannose-ligand receptor expression, acrosome status and membrane cholesterol content.

Normozoospermic men who do not fertilize human eggs in vitro constitute a clearly identifiable class of occult male factor infertility. We have studied the relationships between in-vitro fertilization (IVF) outcomes and the appearance of sperm surface mannose lectin/zona pellucida ligand activity measured by the binding of fluorescein isothiocyanate (FITC)-labelled mannosylated albumin. Of 338 semen specimens with normal profiles, 10 (2.96%) failed to fertilize in vitro (IVF-). Motile spermatozoa from six of these were analysed retrospectively for zona ligand binding activity on the sperm head in relation to acrosome status and the free cholesterol content of their plasma membrane. IVF+ males and fertile donors served as controls. The six IVF- occult male factor cases were distinguished from controls by their failure to show time-dependent increases in the percentage of spermatozoa exhibiting head-directed mannose ligand activity, by the slow loss or apparent increase in membrane cholesterol and by the absence of spontaneous and/or mannose-induced acrosome exocytosis.

Acrosome↗

Carbohydrates and glycoproteins involved in bovine fertilization in vitro.

In the present study, efforts were made towards identifying carbohydrates and glycoproteins involved in bovine in vitro fertilization (IVF). In vitro matured cumulus-oocyte complexes (COCs) were inseminated in the presence of a variety of carbohydrates and glycoproteins to determine which glycoconjugates act as competitive inhibitors of oocyte penetration. Among the carbohydrates and glycoproteins tested, D-mannose, fucoidan, dextran sulfate, and fibronectin were the most potent inhibitors of oocyte penetration (90% or more inhibition), while L-fucose and vitronectin inhibited the penetration rate to a lesser extent (around 50% inhibition). Other carbohydrates caused less than 40% inhibition (i.e., D-galactose, N-acetyl-D-galactosamine, D-fucose, and sialic acid) or were not effective as inhibitors of oocyte penetration (i.e., mannan, N-acetyl-D-glucosamine, dextran, and heparan sulfate). Heparin was the only carbohydrate that significantly increased the penetration rate. To exclude a possible toxic effect on spermatozoa, sperm motility was evaluated over time by means of computer-assisted sperm analysis in the presence of carbohydrates and/or glycoproteins that inhibited the penetration rate with 40% or more. L-fucose, dextran sulfate, and vitronectin did not significantly influence total and progressive sperm motility, whereas D-mannose, fucoidan, and fibronectin caused a significant, but slight reduction in both motility parameters. These results are indicative for the involvement of D-mannose, L-fucose, fucoidan, dextran sulfate, fibronectin, and vitronectin in bovine IVF.

Animals↗

Expression of Bcl-2 and Bax proteins in relation to quality of bovine oocytes and embryos produced in vitro.

The mechanisms underlying the visual assessment and selection of immature oocytes resulting in optimum embryonic development following in vitro maturation, fertilization and culture (in vitro maturation (IVM)/in vitro fertilization (IVF)/in vitro embryo culture (IVC)) are unknown. Also, the reasons for the more frequent occurrence of cytoplasmic fragmentation in in vitro produced bovine embryos, resulting in poor survival following cryopreservation and decreased pregnancy rates following embryo transfer are not clear. The objectives of this study are: (1) to investigate whether differences in the quality of immature oocytes and embryo fragmentation are associated with apoptosis; and (2) to study the pattern of Bcl-2 and Bax expression in oocytes and embryos to help elucidate their potential roles in the regulation of apoptosis during development. Bovine oocytes were obtained from slaughterhouse ovaries and divided into four grades (grades I-IV) based on their morphology. Oocytes of different grades were cultured in serum-free medium for 48h. Embryos were produced only from grade I oocytes (highest quality) via IVM, IVF and IVC procedures. The morphological analysis of apoptosis in oocytes and embryos was carried out using propidium iodide staining and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling. The expression of Bcl-2 and Bax in oocytes and embryos of different qualities and stages was determined using western blotting. The results showed that the number of morphologically abnormal oocytes with shrinkage and/or fragmentation of the ooplasm, which are typical features of apoptosis, was significantly higher in grade IV oocytes (denuded oocytes, the lowest quality) than in grade I oocytes after 48h in vitro culture (P<0.05). DNA fragmentation, a hallmark of the biochemical changes seen in apoptotic cell death, was observed in morphologically fragmented oocytes and embryos. The expression of Bcl-2 was high in good quality oocytes and embryos, low in fragmented embryos, and hardly detectable in denuded oocytes. In contrast, the expression of Bax was found in all types of oocytes and embryos with the highest expression in the denuded oocytes. This implies that the ratio of Bcl-2 to Bax may be used to gauge the tendency of oocytes and embryos towards either survival or apoptosis. Overall, our results show that apoptosis appears to be an underlying mechanism of bovine oocyte degeneration and embryo fragmentation. Interactions between the Bcl-2 family of proteins may play a critical role in pre-implantation embryo development. These findings could have important implications for improving IVF and related techniques.

Animals↗

[Treatment of infertility by in vitro fertilization (IVF-ET)].

The authors survey available publications dealing with the indications for in vitro fertilization, ovary stimulation technique, control of the ovary stimulation, oocytes collection, and transfer of the embryo in human. The authors personal experience with in vitro fertilization is also discussed.

Animals↗

Influence of sperm:oocyte ratio during in vitro fertilization of in vitro matured cumulus-intact pig oocytes on fertilization parameters and embryo development.

The present study was conducted to evaluate the influence of sperm:oocyte ratio during in vitro fertilization (IVF) of in vitro matured cumulus-intact oocytes on fertilization parameters and embryo development in pigs. In vitro matured oocytes surrounded by intact cumulus cells (COC) were inseminated with frozen-thawed spermatozoa at different sperm:oocyte ratios (2000:1, 3000:1, 4000:1, 6000:1, and 8000:1). Denuded oocytes inseminated with 2000 frozen-thawed spermatozoa:oocyte were the control group. A total of 2546 oocytes in five replicates were exposed to spermatozoa for 6 h and then cultured in embryo culture (EC) medium for 6 h (pronuclear formation) or 7 days (blastocyst formation: BF). The penetration rate increased in the COC groups with the sperm:oocyte ratio, reaching the highest rates with 8000:1 spermatozoa:oocyte (72.1 +/- 6.5%), similar to the control (73.5 +/- 3.5%). However, the monospermy was highest with the lower spermatozoa:oocyte rates (82.6-94.8%) and decreased drastically (P<0.05) in the COC group fertilized with 8000 sperm:oocyte (36%). The efficiency of fertilization (number of monospermic oocytes/total number of inseminated oocytes) showed no difference among the COC groups (20-30%) but they were significantly lower (P<0.007) than those obtained by the control group (43.7 +/- 2%). Embryo development was highest in the control group (58% for cleavage and 23% for BF) but not significantly different with the 6000 and 8000 sperm:oocyte COC groups (47 and 50% for cleavage and 19 and 17% for BF, respectively). These results indicate that the use of COC for IVF involves a drop in the efficiency of the fertilization and the necessity to increase the frozen-thawed sperm:oocyte ratio three to four times more to obtain similar embryo development to denuded oocytes.

Animals↗

[Reproductive endocrinology and infertility in the light of 20 years of IVF experience].

In vitro fertilization (IVF)'s results have continuously improved over the past 20 years, making IVF part of routine services offered by most medical communities. The simplification of medical (ultrasound guided oocyte aspirations) and biological techniques (ready made media) contributed to the widespread development of IVF in the private sector, including in Switzerland. This challenges the needs of maintaining academic based IVF programs in the French speaking Switzerland. We believe however that IVF should remain part of academic gynecology because it also brings widespread collateral benefits that serve Gynecology notably, for teaching. Yet, the restricted size the French speaking Switzerland calls for creative approaches.

Endocrinology↗

Pregnancy complications, obstetric risks, and neonatal outcome in singleton and twin pregnancies after GIFT and IVF.

PURPOSE: In vitro fertilization (IVF) and to a lower extent gamete intra-fallopian transfer (GIFT) have become routine infertility treatments in industrialized countries. Our purpose is to compare the obstetric and neonatal characteristics of singleton and twin pregnancies after GIFT and IVF with those conceived spontaneously. METHODS: This case-control study was conducted in a tertiary care medical center. The 322 singleton and 78 twin pregnancies after GIFT or IVF from 1991 through 1996 were evaluated and compared with each other, and with a control group that conceived spontaneously and matched for parity, maternal and gestational age. Statistical significance of differences was assessed by chi(2) test or two-tailed Fisher exact test. Continuous variables were compared by the paired t-test. RESULTS: Pregnancy-induced hypertension (PIH) and vaginal bleeding were significantly more frequent maternal complications in the GIFT/IVF singleton groups compared to controls. In twin pregnancies the rate of cesarean sections, vaginal bleeding and preterm labor were more common after GIFT/IVF but did not reach statistical significance. Assisted reproduction was associated with low birth weight only in twin pregnancies when controlled for confounding variables, however perinatal outcome was comparable. There was no significant difference in the outcome measures between GIFT and IVF pregnancies. CONCLUSION: After controlling for parity, maternal and gestational age, singleton pregnancies conceived by GIFT/IVF are at increased obstetrical risk, however the perinatal outcome is comparable despite a lower average birth weight.

Case-Control Studies↗